Tribulus terrestris is a popular Ayurvedic herb with potency enhancing properties. According
; to the Belgian Royal Decree of 1997, Tribulus is a regulated plant when used in plant food
; supplements. The dangers of self-medication and toxicity of such plant supplements is
; heightened by the ease with which they can be purchased from various illegal channels,
; necessitating an efficient screening approach.
; This study aims to develop a multidimensional approach using chromatographic fingerprinting
; at different wavelengths for identification of Tribulus terrestris in plant food supplements. A
; specific, selective and fast fingerprinting method for Tribulus (reference material obtained from
; the American Herbal Pharmacopoeia) was developed using ultra high performance liquid
; chromatography coupled with a diode array detector. Next, a correlation analysis comparing
; the wavelengths was performed and 5 orthogonal wavelengths were selected. The developed
; method was tested for specificity in different triturations (½0, 1/15, 1/10, ⅕ and ½). These
; were prepared using 10 blank matrices and lactose. In most triturations, Tribulus could visually
; be detected from concentration 1/10 onwards, by comparing the fingerprints with the reference
; plant.
; A market study of a total of 20 samples (with potency enhancement as indication) seized by
; the Belgian Federal Agency for Medicines and Health Products (FAMHP) was carried out.
; Visual inspection was conducted to detect the presence of Tribulus in the real samples. This
; was done by overlaying the sample chromatograms with the reference plant and visually
; comparing the fingerprints. So, out of 20 samples, 11 samples were suspected to be positive,
; when analyzed at the 5 wavelengths, 254 nm and with the combined fingerprint. The multi and
; combined wavelengths approach provides a characteristic and specific fingerprint with more
; information at different wavelengths than only 254 nm, which is useful for visual inspection. In
; a second step, mass spectrometric (MS) measurements using a time of flight analyzer were
; performed. This was done in order to further confirm the presence of Tribulus in suspected
; samples. After obtaining MS fingerprints, the exact mass of the main peaks (peaks with the
; highest absorbance in the reference) were compared. It was concluded that out of 11 samples,
; 9 can be suspected to be positive for Tribulus terrestris. As future prospects, steps are being
; taken to combine chromatographic fingerprinting and chemometrics in order to use these
; multidimensional data and extract maximum information with the intention to create binary
; models for faster screening of plant food supplements.